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    <title>Peak detection - Deconvolution - Savitzky-Golay</title>
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<h1>Chromatogram deconvolution</h1>

<h2>Savitzky-Golay</h2>

<p>
    This method uses the Savitzky-Golay polynomial (A. Savitzky and M. J. E. Golay, <em>Anal. Chem.</em>,
    <strong>36</strong>, 1627 (1964)) to calculate the smoothed second-derivative of the chromatogram's intensities. The
    following figure (left) presents the shape of (a) a Gaussian peak, (b) the first derivative, and (c) the second
    derivative. The figure on the right side shows how the signal (blue line) may be divided into individual
    chromatographic peaks by observing the second derivative.
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<p>
    <img src="1nd2ndDerivative.jpg" alt="Savitzky-Golay filter">
    <img src="1nd2ndDerivative2.jpg" alt="Savitzky-Golay result">
</p>


<h4>Method parameters</h4>

<dl>
    <dt>Min peak height</dt>
    <dd>Minimum acceptable peak height (absolute intensity)</dd>
    <dt>Peak duration range</dt>
    <dd>Range of acceptable peak durations</dd>
    <dt>Derivative threshold level</dt>
    <dd>Minimum acceptable intensity in the second derivative for peak recognition</dd>
</dl>

<p>
    <img src="savitzky_golay.png" alt="Savitzky-Golay example">
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